1. Field of the Invention
The present invention relates to novel neocarzinostatin complexes, more particularly to neocarzinostatin complexes represented by the following formula (I): EQU (SMA).sub.n --(NCS) (I)
wherein n is an integer of 1-35, NCS represents neocarzinostatin residue, SMA represents a residue of a half esterified styrene-maleic acid copolymer having an average molecular weight of 1,000-10,000 in which the maleic acid portion consists of the following units.
(1) maleic acid residue bonded to NCS ##STR1##
(2) maleic acid residue which is free or bound to NCS by non-covalent bonding ##STR2## provided that the total amount of the above described maleic acid residues (1) and (2) is from an average content of 0.1 per molecule to 60 mol % of SMA, and
(3) half-esterified maleic acid residue ##STR3## wherein R is a monohydric alcohol residue or a residue of monohydroxyalkyl ether of di- or trihydric alcohol, and a method for producing the same.
Neocarzinostatin is a proteinic anticarcinogen produced in a media in which Streptomyces carzinostaticus var. F-41 Kuroya is cultured (Japanese Patent Publication No. 42 (1967)-21752 and U.S. Pat. No. 3,334,022). With respect to the primary structure of this substance, the total number of amino acid residues and estimated molecular weight have been reported to be 109 and 10,700 respectively, by Hiroshi Maeda who is one of the present inventors (Science, 178, 875-876 (1972) and Arch. Biochem. Biophys., 163, 379-385).